Step 1

Step 2

After pressing that button we can see this:

App Name: The name of the app, using no more than 32 characters and no less than 3. Please make sure that your app name does not violate the trademark or other rights of a third party. Otherwise, we may be forced to remove your app.App Namespace: The app namespace is used for defining custom Open Graph actions and objects (e.g., namespace:action) and for the URL for Apps on Facebook (e.g., http://apps.facebook.com/namespace)App Category: Choose the category that best describes your app. Be sure to read our category guidelines.

Step 3

After filling the captcha, you can see the settings page. From here you need the App ID and the App Secret.